Electronic data can be modified relatively easily and without leaving much of a trace. As organizations increasingly rely on electronic data, it is important to protect these data from improper modification. One way of protecting the data from modification is to store the data in Write-Once-Read-Many (WORM) storage.
Many business entities rely on some form of WORM storage to store critical data. In many industries, such as the financial services and healthcare industries, businesses are required by strict records-retention regulations to archive important data, such as emails, transaction information, patient records, audit information, as well as other types of documents and data. In addition, many business entities place a premium on protecting certain business records or critical data files from accidental or intentional alteration or deletion. WORM functionality such as non-erasable and non-rewritable data storage can ensure long-term data permanence, even where regulatory compliance does not require the use of WORM storage.
Traditionally, WORM storage is implemented using optical storage where the storage media is inherently write-once. However, optical recording has not been improving at the rate of magnetic recording so that it has become relatively expensive to store data in optical storage. Moreover, what is increasingly required in practice is to protect individual pieces of data (records, files, emails, data objects, etc) from modification for some specified retention period.
Several systems that protect individual pieces of data from modification for some specified retention period have been introduced recently, such as, for example, the Centera from EMC, the Data Retention 550 from IBM and the SnapLock from Network Appliance. The EMC Centera and IBM Data Retention 550 use their own non-standard interfaces to allow a user or application to specify that a data object should be protected from change for some duration. They require applications to be written specifically to their own interfaces. The Network Appliance SnapLock overloads selected attributes in standard file system interfaces to flag a file as WORM and to associate a retention period with the file. It, however, uses multiple attributes and requires multiple operations so the act of setting the retention period and committing a file to be WORM may not be atomic and is unnecessarily complex and costly.